The invention relates to an airplane, preferably a helicopter, of the type driven by a piston type internal combustion engine arranged within the walls of a cabin
In British Pat. (GB-PS) No. 723,452, a vertically standing, horizontally opposed internal-combustion "boxer type" engine is shown that drives a rotor of a flying apparatus.
British Pat. (GB-PS) No. 585,317 shows an internal-combustion engine of an airplane, also of horizontally opposed piston construction, the cylinders of which are arranged in a horizontal position.
It is an object of the invention to provide such arrangements and take such measures at a helicopter that is driven by an internal-combustion engine that, while a good intake air supply is ensured, the internal-combustion engine and its assemblies are reliably supplied with cooling air also under extreme operating conditions.
According to the invention, this objective is achieved by installing the engine horizontally in the helicopter cabin and by providing cooling air inlet opening means at a side wall of the cabin.
The main advantages achieved by means of the invention are that the cooling blower and the suction system of the internal-combustion engine are supplied with the respective medium--cooling air, intake air--in a simple and advantageous way, in which case the existing pressure difference between the side wall and the underside of the cabin is utilized effectively for the disposal of the used-up cooling air. The air inlet opening at the longitudinal sides of the cabin, via which a sufficient amount of air enters, can be integrated into the side walls of the helicopter without any problems. The guiding ducts, the pipe system and the outlet duct are easily manufacturable parts and may be installed in the cabin without difficulty.
Cooling air flows through the coolers--the oil cooler and/or the charge air cooler in an operationally adequate manner in preferred embodiments of the invention. An auxiliary blower is provided in certain preferred embodiments that is driven by the internal-combustion engine to ensure that in an extreme flying situation, for example, during hovering, the coolers are sufficiently acted upon by cooling air.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.